Revisiting the developmental stage and age-at-death of the "Mrs. Ples" (Sts 5) and Sts 14 specimens from Sterkfontein (South Africa): do they belong to the same individual?
During the 1947 fieldwork season, Member 4 (2-3 My) of the South African Sterkfontein site yielded two important Australopithecus africanus fossils: a cranium popularly nicknamed "Mrs. Ples" (Sts 5), and a partial skeleton (Sts 14). Previous reports have proposed that Sts 5 was a nonfully grown adolescent individual (Thackeray et al., S Afr J Sci 2002a;98:21-22), and that Sts 14 was a sub-adult specimen (according to various signs of immaturity in the skeleton) (Berge and Gommery, C R Acad Sci Paris, Sciences de la terre et des planètes 1999;329:227-232; Häusler and Berger, J Hum Evol, 2001;40:411-417; Thackeray et al., S Afr J Sci, 2002b;98:211-212). It was subsequently proposed that these fossils actually belonged to the same individual (Thackeray et al., S Afr J Sci, 2002b;98:211-212), a proposition supported by their spatial positions within the site. The present work attempts to revise these different assertions. The results obtained: (i) show that the Sts 5 fossil represents a fully grown adult cranium; (ii) provide new evidence of immaturity in the Sts 14 skeletal elements (sustaining the proposed young adult age of this specimen), and (iii) suggest that although the revised ages-at-death for these fossils are partially compatible, there is no evidence to support the idea that they represent a single individual. Finally, the encephalization quotient associated with a hypothetical union of Sts 5 and Sts 14 (calculated using data from both specimens) lies between the upper and lower limits of the currently estimated range for this species and H. habilis, respectively.
Bonmatí
Alejandro
A
Centro de Investigación (UCM-ISCIII) de Evolución y Comportamiento Humanos, c/Sinesio Delgado 4, 28029 Madrid, Spain. abonmati@isciii.es
Arsuaga
Juan-Luis
JL
Lorenzo
Carlos
C
D000375:Aging / Q000502:physiology; D000818:Animals; D000885:Anthropology, Physical / Q000379:methods; D000886:Anthropometry / Q000379:methods; D005075:Biological Evolution; D001846:Bone Development / Q000502:physiology*; D001842:Bone and Bones / Q000033:anatomy & histology*; D005260:Female; D015186:Hominidae / Q000033:anatomy & histology* / Q000254:growth & development*; D008136:Longevity / Q000502:physiology; D010163:Paleontology / Q000379:methods; D002679:Pan troglodytes / Q000033:anatomy & histology / Q000254:growth & development; D012863:Skeleton; D012886:Skull / Q000033:anatomy & histology / Q000254:growth & development; D013019:South Africa; D013045:Species Specificity; D013131:Spine / Q000033:anatomy & histology / Q000254:growth & development